What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
Instructional flight. Aircraft landed kxll rwy 25, departed left edge of runway just past intersection, impact low snowbank.
Elevator, aileron, rudder, and nose wheel steering systems intact and continuous.
Tire pressures are nose 18, left 45, right 42. Left tire shows one small reversionary patch. Right tire is unremarkable. Nose tire shows continuous circumferential scuff on left edge of tread.
Observed aircraft damage includes: left gear trunnion fractured between oleo tube and rear pivot bearing, fwd pivot bearing carrier fractured, aft trunnion bearing carrier bulkhead bent, skin above trunnion punctured by trunnion and deformed by bulkhead , nacelle deformed due to supporting skin deformation, skin and bulkhead behind left gear deformed due to contact with torque links, gear door bent and rod broken; but gear still supporting aircraft. Nose gear collapsed due to failure of drag link at impact with snowbank. Collision damage to nose cone and gear doors from impact with snowbank. Both propellers have one blade each bent approx midspan, with very little rotational scratching on tips.
Skid marks on runway leading to impact site show aircraft was tracking straignt down runway and approximately on centerline but was in significant left crab (nose and left skid marks significantly closer together than to right skid mark) before hooking left and departing runway.
Close examination of fractured left gear trunnion shows 45 degree brittle overload fracture signatures typical of overload failure. The surfaces were not pristine, due to some smearing from parts rubbing together during recovery and dissassembly, but no indication (beach marks or chevrons) of pre-existing fracture was found.
As the FAA filed it
INSTRUCTIONAL FLIGHT. AIRCRAFT LANDED KXLL RWY 25, DEPARTED LEFT EDGE OF RUNWAY JUST PAST INTERSECTION, IMPACT LOW SNOWBANK.
ELEVATOR, AILERON, RUDDER, AND NOSE WHEEL STEERING SYSTEMS INTACT AND CONTINUOUS.
TIRE PRESSURES ARE NOSE 18, LEFT 45, RIGHT 42. LEFT TIRE SHOWS ONE SMALL REVERSIONARY PATCH. RIGHT TIRE IS UNREMARKABLE. NOSE TIRE SHOWS CONTINUOUS CIRCUMFERENTIAL SCUFF ON LEFT EDGE OF TREAD.
OBSERVED AIRCRAFT DAMAGE INCLUDES: LEFT GEAR TRUNNION FRACTURED BETWEEN OLEO TUBE AND REAR PIVOT BEARING, FWD PIVOT BEARING CARRIER FRACTURED, AFT TRUNNION BEARING CARRIER BULKHEAD BENT, SKIN ABOVE TRUNNION PUNCTURED BY TRUNNION AND DEFORMED BY BULKHEAD , NACELLE DEFORMED DUE TO SUPPORTING SKIN DEFORMATION, SKIN AND BULKHEAD BEHIND LEFT GEAR DEFORMED DUE TO CONTACT WITH TORQUE LINKS, GEAR DOOR BENT AND ROD BROKEN; BUT GEAR STILL SUPPORTING AIRCRAFT. NOSE GEAR COLLAPSED DUE TO FAILURE OF DRAG LINK AT IMPACT WITH SNOWBANK. COLLISION DAMAGE TO NOSE CONE AND GEAR DOORS FROM IMPACT WITH SNOWBANK. BOTH PROPELLERS HAVE ONE BLADE EACH BENT APPROX MIDSPAN, WITH VERY LITTLE ROTATIONAL SCRATCHING ON TIPS.
SKID MARKS ON RUNWAY LEADING TO IMPACT SITE SHOW AIRCRAFT WAS TRACKING STRAIGNT DOWN RUNWAY AND APPROXIMATELY ON CENTERLINE BUT WAS IN SIGNIFICANT LEFT CRAB (NOSE AND LEFT SKID MARKS SIGNIFICANTLY CLOSER TOGETHER THAN TO RIGHT SKID MARK) BEFORE HOOKING LEFT AND DEPARTING RUNWAY.
CLOSE EXAMINATION OF FRACTURED LEFT GEAR TRUNNION SHOWS 45 DEGREE BRITTLE OVERLOAD FRACTURE SIGNATURES TYPICAL OF OVERLOAD FAILURE. THE SURFACES WERE NOT PRISTINE, DUE TO SOME SMEARING FROM PARTS RUBBING TOGETHER DURING RECOVERY AND DISSASSEMBLY, BUT NO INDICATION (BEACH MARKS OR CHEVRONS) OF PRE-EXISTING FRACTURE WAS FOUND.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.